To provide a wide surface roughness concrete-paving plate by spraying a delay agent to the surface of unhardened concrete placed in a form, repeatedly flattening the surface by rubbing with a trowel, and continuously repeating the delay agent spray and trowel flattening processes at a required number of times.

Generally, concrete obtained by mixing Portland cement, water, fine aggregate (sand) and coarse aggregate (gravel) is placed, a hardening delay agent is added to the surface, the surface is flattened by rubbing the surface several times with a flat trowel, the hardening delay agent addition and trowel flattening processes are repeated at a required number of times (about three times), it is left as it is half a day (concrete of a part where a hardening delay agent does not yet permeate is hardened), and the unhardened part of the surface is washed for a required time. Thus, as the amount of a delay agent added is increased, a concrete-paving plate with a larger surface roughness is obtained, and it is possible to obtain a concrete-paving plate with a roughness far exceeding a sand patching value of 1 mm.